Shift key mechanism for accordions



Jan. 5, 1937.

4&

4 M. B. LUTTBEG 2,066,633

SHIFT KEY MECHANISM FOR ACCORDIONS Filed Aug. 12, 1935 3 Sheets-Sheet l Jan. 5, 1937. M. a. LUTTBEG SHIFT KEY MECHANISM FOR ACGORDIONS Filed Aug. 12, 1935 I5 Sheets-Sheet 2 Irwmiw" K flag: Biaiidey Patented Jan. 5, 1937 UNITED STATES PATENT OFFICE Application August 12,

12 Claims.

This invention relates generally to accordions and more particularly to shift key mechanism for changing or varying the tone effects of the accordion.

5 The better class of accordions is generally equipped with means for shutting off certain groups of reeds of the treble section, thereby producing various tone effects. Thus in an accordion, the treble section of which has four 10 reed trays or blocks, the following tonal changes can be produced by using two shift keys to close certain of said reed blocks:

(1) Flute oboe,

(2) English horn bandonion,

(3) Violin effect,

(4) Natural accordion tone, low octave.

Heretofore, such an accordion had the shift keys arranged generally on the edge of the keyboard at right angle to the keys or on the rear side thereof and they were operated by the palm of the player's right hand which had to be moved from its regular position on the keyboard and the pressure had to be on the back part of the strip or shift key so as to force it rearwardly in order to operate the shifting mechanism which is mounted on the back of the keyboard. This proved very inconvenient as it interfered with the regular playing movements of the player and caused strain on the hand due to the unnatural 30 position thereof as the arm had to be held close to the body. The shift keys were arranged longitudinally of each other due to the narrowness of the keyboard. Furthermore, the shift keys were so located that they easily caught on the 35 coat or sleeve of the player or accidentally became actuated when the accordion was held close to the body of the player.

One of the objects of the present invention is to provide an accordion in which the shift keys are located on the front of the accordion adjacent to and substantially in the same plane with the keys of the treble keyboard so that such shift keys can be actuated by the tips of the fingers without requiring the players hand to be 4 3 moved from its regular playing position.

Another object of the invention is so to arrange the shift keys that they can be easily operated during the playing operation to change the playing tone of the accordion from a lower octave to a higher octave, and vice versa, thereby enlarging the playing scope of the accordion.

Other objects of the invention are to provide novel means for operating the reed tray valves or slide plates with the shift keys positioned for- 55 wardly of and substantially in the same plane 1935, Serial No. 35,770

with the keys of the treble keyboard so that said shift keys can be operated with the same ease and in the same manner as the keys of said keyboard.

Still other objects of the invention are to provide novel and efficient means for sealing the operating connection between the shift key mechanism and the reed section so as to prevent leakage of air from the latter.

With these and other objects in view, my invention consists in certain novel features of construction and arrangement of parts, hereinafter more fully described and claimed, and illustrated in the accompanying drawings, in which Figure 1 is a. front elevational view of my improved accordion.

Figure 2 is a full-sized detail view of the shift key mechanism with the keyboard partly broken away.

Figure 3 is a top plan view of the treble reed section with the reed trays partly broken away.

Figure 4 is an enlarged cross section taken on line 4--4 of Figure 3.

Figure 5 is an enlarged fragmental cross section taken on line 5--5 of Figure 1.

Figure 6 is a fragmental front elevational view of the part shown in Figure 5.

Figure '7 is a horizontal cross section taken on line l-'l of Figure 2.

Figure 8 is an enlarged fragmental cross section of one of the reed trays and the slide plate therefor.

Figure 9 is an enlarged detail view of the indicator.

Figure 10 is a side elevational view of same.

Figure 11 is an elevational view of another form of shift mechanism attached to the treble section.

Figure 12 is a side elevational view of same with parts of the accordion broken away.

Figure 13 is an enlarged transverse cross section taken on linel3-l3 of Figure 11.

Figure 14 is an enlarged cross section through the indicating means.

Figure 15 is an enlarged detail view showing the connection between one of the shift keys and the shift mechanism. I

Referring by numerals to the accompanying drawings, l0 indicates an accordion having a bellows section li, a bass section l2, and a treble section M. The treble section is provided with a keyboard IS on the front of which are mounted keys IS. The latter operate in the usual manner a suitable mechanism by means of which valves or clappers I1 open and close valve openings is formed in a sound-board II. This sound board is arranged in one end oi the treble section It.

This section It is box-shaped having side walls 2| and end walls 2|, the sound board I! being arranged to one side oi said section ll while the other side oi said section is open and is connected to the corresponding end oi the bellows H.

The apertures is are arranged in a series of rows, as shown in Figure 3 and each row or group oi apertures has arranged thereabove a corresponding tray 22, each oi which is provided with a plurality of reeds (not shown). As shown in the drawings, there are five sets oi trays, arranged parallel with each other, in said treble section I. The inner trays 22a, 22b, and lie are double, each containing two sets of reeds, while the outer ones are single and having each, one set oi reeds. The trays are constructed in the usual manner and have reeds arranged in the side walls and having the lower ends open and fitting close against the inner iace oi the sound board l8 in such a manner as to enclose the corresponding row of apertures ii.

The inner trays 22a, 22b, and 220 are each provided with a slide plate or valve 24a, 24b, and 0, respectively. These plates are slidably mounted in the bottom or lower end oi each tray and each plate is provided with a plurality oi apertures 25 which are so spaced that when the plate is in one position said apertures register with the corresponding row of apertures l8 and when said plate is moved in the opposite direction said apertures 25 are disposed with the corresponding apertures is, thereby closing the communication between the trays and said apertures I 8.

As stated before, there are four tone eiiects or changes that can be obtained in the instrument, namely, flute oboe, English horn bandonion, violin effect, and natural or accordion eiiect. In the instant case, two shift keys 26 and 21 are used. As shown in Figure 1, these shiit keys are arranged parallel with each other immediately in front 0! the keys and are disposed above the gallery or cover 28 which is attached to the keyboard section I 4 and encloses the clappers arranged therein. The shift keys are pivotally mounted at each end in blocks 28 which are fixed to the sound board IS. The keys or bars 26 and 21 have fixed to their undersides fingers or projections 30 and ii, respectively. Projection 30 bears against one end of an arm 32. the other end oi which is fixed to or iormed integral with a shaft 34. This shait has bearing and extends through the keyboard and receives on its opposite end an arm 35.

The downward extension or finger II of lever 21 engages one end of an arm 38, the opposite end oi which is fixed to or formed integral with a shaft 31 which is revolubly mounted in and extends through the keyboard II and receives on its opposite end an arm 30. Arms 35 and II extend toward each other, as shown in Figure 2, and are spaced a suitable distance from each other. The inner end of arm 3! has pivotally connected thereto the lower end of a link 39 and the upper end 01' said link is pivotally connected to a sliding bar 40, as indicated at 4|. This sliding bar is mounted on the rear side oi keyboard II by means of screws 42 which engage longitudinal slots iormed in said bar. A spring 44 has tendency to hold the bar I in outward position. The lower or inner end oi said bar has pivotally connected thereto, as indicated at II. the upper or outer end oiatripper. Aspringintheiormoiaspring wire 41 is fixed to bar 40 and extends longitudinally thereirom and engages at 0 said tripper ll, thereby yieldingly holding said tripper in longitudinal alignment with said bar 4..

The lower or inner end or tripper I! is enlarged as indicated at I and is provided with a pair oi transversely disposed downwardly presented shoulders a 1111s enlargement 4| overlaps the upper end oi an oscillstable member ll which is pivotaliy mounted at II to said keyboard II at a point which is longitudinally aligned with bar ll. This oscillatable member is oi T-shape and has the ends 01' its cross bar "a rebent, as indicated at llb. Them rebent portions are so arranged with respect to shoulders "a that when said tripper It is moved downwardly one oi said shoulders engages the corresponding rebent portion 50b and rocks said member II. The lower end of oscillatable member ll extends downwardlyorinwardlypastsaidkeyboard llandterminates adjacent to one oi the side walls I. oi the treble section ll. A rod 82 is fixed at one end to said end of member ll and extends through a slot is iormed in said wall ll inwardly into the treble section [4, as shown in Figure 3.

Pivotally fixed to the inner end oi bar I! is one end oi a rod ll. This rod extends longitudinally toward one end of said section and is pivntally connected to an arm II which extends downwardly irom and is fixed to a horizontally and transversely disposed shnit II. This lhait is iournaled in bearings II which latter are mounted on a block II which is fixed to one oi the end walls II and extends a suitable distance above the sound board It. An arm I is fixed at its upper end to shit I! while the lower end oi said arm engages an aperture iormed in one end oi slide plate Ilb, which latter is slidably mounted in reed tray 22b.

Arm" whichisfixedtoshaitfl andisoperated by shiit key 21 is connected by a link Ila to a bar "a which operates, through a trlpper a, oscillatable member I! which is similar in shape and operation to member l. The lower end oi member ll has fixed thereto 8 rod N which extends through a slot I in wall 2| into the treble section I. The inner end oi this rod 54 has pivotally fixed thereto a rod or connecting link '6. This rod is arranged parallel with rod I! and is pivotally connected at its other end to an arm 61 which extends downwardly irom and is fixed to a shsit II. This shait is disposed parallel with shait I1 and is iournsled in bearings ll. An arm 00 is fixed to shait II and extends downwardly thereirom and engages an aperture iormed in the plate or valve c which is slidably mounted in the reed tray 22c. Similarly,arodorarmllisfixedtosaidshait I on the opposite side of arm Cl and the lower end oi said arm ll engages an aperture formed in one end oi the plate or slide valve 24 which is slidably mounted in the reed tray 22a.

In order to prevent escape oi air through slots 54 and II, a section oi fiexible material, such as thin leather H, is cemented or glued along its edges to the inner isce oi wall 2.. AJeather washer ll oi suitable thicknessis arranged on each rod 52 and I4 adjacent to the corresponding ends oi connection rods ll and l. Member 14 is apertured at appropriate points and the edges oi said apertures are cemented or glued to the respective washers ll so as to provide an 7 aoeaoas air-tight seal. The flexible member I4 permits movement of bars 62 and 64 and at the same time forms a seal therefor.

An indicating means I6 is provided to enable the player to ascertain easily the positions of the slide plates 24a, 24b, and 240. This indicating means is preferably located adjacent to the upper end wall 29a of cover or gallery 29, there being a window 11 formed in said end wall through which said indicating means is visible. As shown, this means consists of a stationary chart I9 divided longitudinally into two zones 19a and 1917, each of which is divided into two sections. The sections of the upper zone 19b carry indicia 3 and I which corresponds, respectively, to the flute oboe and violin effect. The lower field I9 is marked "low octave and the sections carry indicia on and "03.

A pointer I9 is mounted to operate over field 19a and is operated when the shift key 26 is depressed. A connecting link 89 is connected at one end, as at M, to pointer I9 and at the other end to oscillatable member 59 as indicated at 92 so that said pointer is moved by and in accordance with the positioning of said member 59.

A pointer 84 is mounted to operate over zone 19!; and has connected to it one end of a link 85 as indicated at 86, while the other end of said link is connected to os'cillatable member 62 as indicated at 91.

A pad or cover 98 is secured to the underside or back of keyboard I5 and protects the mechanism mounted thereon. A lining 99 of felt or other suitable material is arranged on the inner side of sound board I9 to provide a soft bed for receiving the reed trays and forming an airtight seal therebetween and said sound board.

The shift keys 26 and 21 are arranged immediately back of the keys I6 so that they can be easily operated by the tips of the player's fingers without requiring the players hand to be removed from its normal playing position on the keyboard. By this arrangement of the shift keys, the tone effects of the accordion can be readily changed without interrupting the playing of the accordion and the player can readily change from low octave to high octave and vice versa during the playing operation. The shift keys can be of any desired shape and size and they can be arranged in a single row or otherwise spaced with respect to each other, the main object being to mount them adjacent to the keys and in such a manner that they can be easily operated.

The blocks 29 on which the shift keys are mounted are arranged on the soundboard I9 in such a manneras'not to interfere with the clappers H or their connections. The links 39 and 39a and their connections permit the operation of the mechanism mounted on the back of the keyboard by means of said shift keys 26 and 21.

Springs 44 and 44a serve to restore members 49 and 4911, links 39 and 39a, and parts associated therewith, including shift keys 26 and 21, tonormal positions after'each operation. Members 59 and 62, plates 24a, 24b, and 240, indicators I9 and 94, and their respective connections, remain in their last operative positions until the next operation.

Keys 26 and 21 and the shift mechanisms operated thereby are so arranged that they do not interfere either with the keys I6 and their operation, or the clapper mechanism actuated by said keys.

When all of the plates 24a, 24b, and 24c are open, as in Figure 3, the accordion produces natural or accordion tone and the indicator I9 points to the legend "on and indicator 94 to 9 (see Fig. 9). a

To obtain violin eflect, shift key 26 is actuated whereby the plate 24b is moved into closed position. The reed tray 22b is now closed and only reed trays 22, 22a and 220 are active. The indicator I9 points to of!" while indicator 94 remains at "3".

In the English horn bandonion effect, shift key 21 is actuated to close plates 24a and 240 and shift key 26 is actuated (if plate 24b occupies closed position) to open plate 24b so that reed trays 22 and 221: are active and reed trays 22a and 220 are closed or inactive. The indicator I9 points to on and indicator 94 points to I".

when it is desired to obtain flute oboe eflect, keys 26 and 21 are operated to close plates 24a, 24b, and 240 so that the reed trays 22a, 22b, and 22c are closed and only reed trays 22 are active. Indicator I9 is at "off" and indicator 94 is at 1 position.

An important feature of the present invention is the fact that the player is able with a. little practice to shift, without interruption, from the low compass to the high octave while performing on the instrument. Thus a whole octave in the range of the keys is gained while playing up the scale and another octave is gained by going down the scale. All that the player is required to do is to press key 26 to bring the pointer I9 to on position for low octave and to operate a shift key pivotally mounted on said sound board octave.

In the form shown in Figures 11 to 15, inclusive, a pair of shift mechanisms 99 for actuating the plates 24a, 24b and 240 is mounted on one of the side walls 29 of treble section I4. As in the previously described form the plates 24a and 240 are actuated simultaneously by one shift mechanism while the plate 24b is actuated by the other shift mechanism. I

In the present form, each mechanism 99 is simplified in construction and is reduced in size and condensed so that the two mechanisms can be arranged in tandem longitudinally of the major axis of said wall, while in the previous form the mechanisms are arranged in parallel with each other and transversely of the keyboard.

Each shift mechanism 99 consists of a longitudinally movable member 9I to one end of which is connected one end of a rock arm 92. This rock arm is fixed to a rock shaft 94 which is journaled transversely in the keyboard I5 and has mounted on its forward end an arm 95 operable by a finger 96 of one of the shift keys 91.

Pivotally mounted on the other end of member 9I is one end of a finger or tripper 99. This finger extends longitudinally from member 9| and is yieldably held in alignment therewith by a spring wire 99 which latter also serves to restore the parts to normal positions after each operation.

Each finger 99 tapers outwardly and terminates adjacent to a V-shaped end I99 of an oscillatable or bell crank member IN. This member is pivotally mounted in one of the walls 29, as indicated at I92, and is provided at its end adjacent to said finger with a V-shaped notch I99a arranged to each side of said V-shaped end I99. The other arm I94 of member I9I is disposed substantially transversely of the axis of the mechanism and has fixed thereto one end of a pin I95. This pin extends into section I4 through an arcuate slot I96 formed in side wall 29. The

inner end of pin II! has connected thereto in one case one end of a connecting link I" and in the other case one end of a connecting link I00. Said links I01 and I00 are connected to the arms of the respective rock shafts l1 and 00 which in turn are operatively associated with sliding plates 24a, 20b, and 200.

When one of the members Si is actuated by the depression of the corresponding shift key, the finger 06 carried by said member Si is moved forwardly against the V-shaped end I00 and is deflected thereby to one side into one of the V-shaped notches I004. Said member III is thus moved on its pivot I02 in appropriate direction, thereby moving arm I04 from one position to another. This in turn actuates the connecting rod I01 or I00 as the case may be and the corresponding rock shaft 50 or 01 so that the corresponding plates 24a. and Me or plate 24b are moved to open or close the respective reed trays in the same manner as hereinbefore described.

Each member 0| has a transverse extension 0|a which terminates against the underside of the keyboard IS. A rod I09 connects one of the extensions with an arm IIO which is fixed to one end of a rock shaft I II and a rod I I2 connects the other extension Sla with an arm Ill fixed to a sleeve H5. This sleeve is loosely mounted on shaft III and both are journaled in an aperture formed in said keyboard. The other ends of said shaft II I and sleeve I I5 extend to the opposite or key side of the keyboard. An indicating chart II 5 similar to chart I6 is arranged on this side of the keyboard and a window H1 is formed in the end wall 20a of cover 20 to render said chart visible.

Each shift mechanism 90 is provided with a spring 9"), one end of which is anchored to the wall 20 and the other end of which is fixed to member 9|. This spring serves to restore the member SI and parts connected thereto to normal position after each operation.

Fixed to the projecting end of sleeve H5 is a pointer II 8 and fixed to the projecting end of shaft III is a pointer H9. These pointers cooperate with the indicia on chart Hi to indicate the disposition of the various plates of the reed trays in the same manner as hereinbefore described. A cover I20 is attached to section I4 and the other side of keyboard I! to enclose the shift mechanism and parts connected therewith.

I claim:

1. In an accordion, the combination with a treble reed section, a keyboard including a plurality of keys, a plurality of reed trays, and a slide valve plate for each tray for shutting oil. and opening the same, of a shift key mounted on said treble reed section inwardly of said keys whereby said shift key can be operated by the finger tips of the player's hand and a mechanism operable by said shift key and operatively associated with said slide valve plate for moving it at each operaticn of said shift key alternately into closed and open positions.

2. In an accordion, the combination with a treble reed section having a sound board, a keyboard including a plurality of keys, a plurality of reed trays in said section, and a slide valve plate for each tray for shutting off and opening the same, of a shift key mounted on said sound board longitudinally of said accordion and inwardly of said keys, a horizontally disposed rock shaft transversely mounted near one end of said reed section, a rock arm fixed at one end to said shaft and having its opposite end engaging one end aoeasas of said slide plate, and s mechanim associated with saidshift keysndssidshartforalternstsly moving said slide piste into open and closed positions.

3. In an accordion, the combination with s treble reed section having a sand board, a keyboard including a plurality of keys. a plurality of reedtraysinsaidsectiomandsslidevalveplate for each tray for shutting off and opening the same, of s shiftkeymoimted on said sound board and disposed inwardly of said keys whereby said shiftkeyisadsptedtobeoperstedbytheiinger tips of the player's hand without removing said handfromitspositiononssidheyboardshori- :zontally disposed rock shaft transversely mounted .near one end of said reed section. a rock arm fixed at one end to said shaft and having its opposite end engaging one end of said slide plate, amechanism associstedwithssidshift key and said shaft for alternately moving said slide plate into open and closed positions, and an indicating means operatively connected to said mechanism and operable thereby to indicate the position of said plate.

4. In an accordion ofthe character described, the combination with a keyboard, a plurality of keys on said keyboard, a sound board provided with a plurality of openings, a plurality of reed trays arranged on said sound board. and a valve plate slidably mounted in each tray for opening and closing the communication between said tray and the openings in said sound board, of a pinrality of shift keys mounted on said sound board disposed thereabove inwardly of said keys. whereby said shift keys can be actuated by the finger-tips of the player's hand, a mechanism operable by each of said shift keys and connected to certain of said valve plates for moving the latter into and out of register with said openings.

5. A shift mechanism for accordions comprising in combination a reed section, a soundboard having a plurality of apertures closing one end of said section, a plurality of reed trays disposed in said reed section and enclosing said apertures, an apertured plate slidably mounted in certain of said reed trays for opening and closing the communication between the tray and the corre-. sponding apertures in said board, means for operating said plate, said means including a pin extending through a slot in the wall of said reed section, a bell crank operatively mounted on the exterior of said wall and having one arm timed to said pin and having the other arm formed with s V-shaped end having a notch at each side, a longitudinally movable member mounted on said wall of said section, a finger pivotally mounted at one end on said member and having its other end terminating adjacent to said V-shaped end of said bell crank and adapted to be deflected into either notch for rocking said bell crank and operating said plate, a shift key. and means connecting said shift key with said longitudinally movable member for operating the same.

6. A shift mechanism for accordions comprising in combination a reed section including a soundboard having a plurality of apertures arranged in groups, a plurality of reed trays sr-' ranged in said section for enclosing said groups of apertures, an apertured plate slidably mounted in certain of said reed trays for opening and closing communication between said trays .snd the corresponding groups of apertures, means in said reed section for operating'said pistes, said means including a pin extending outwardly from the wall of said section, a bell crank mounted exteriorly on said wall and having a transverse arm secured to the outer end of said pin, the other arm of said bell crank being formed with a V-shaped end having a notch arranged at each side thereof, a longitudinally movable member mounted on said section and movable relatively to said bell crank, a finger pivotally mounted at one end on said movable member and having its other end presented toward the v-shaped end of said bell crank and adapted to enter either of said notches to rock said bell crank, a shift key, means connecting said shift key with said longitudinal member, and a spring for restoring said longitudinal members and parts associated therewith to normal positions.

7. In a shift mechanism for accordions, a shift key, a longitudinally movable member, means connecting said shift key with said movable member and actuating the same, a finger pivotally mounted on said movable member, a bell crank pivotally mounted adjacent to said finger and having one arm disposed longitudinally and formed with a V-shaped end provided with a notch at each side, said finger being movable by said longitudinal member toward said bell crank and being adapted to be deflected by said V-shaped end into one of said notches, thereby rocking said bell crank, a reed tray, an apertured plate slidably mounted in said tray, and connections between said plate and said bell crank for actuating said plate upon each operation of said shift key.

8. In a shift mechanism for accordions, the combination of a reed section, a reed tray mounted therein, an apertured plate slidably mounted in said reed tray for opening and closing communication therewith, a bell crank pivotally mounted on said reed section and having one arm disposed longitudinally thereof and the other arm transversely, means connecting said plate with said transverse arm, a longitudinally movable shift member mounted on said reed section, a finger pivotally mounted at one end on said shift member and having its other end adapted to engage said longitudinal arm to either side of the longitudinal axis thereof, thereby rocking said bell crank from one extreme position to the other, a spring for yieldably holding said finger in longitudinal position, a shift key for actuating said shift member, and means for restoring said shift member and parts associated therewith to their normal positions.

9. In an accordion of the character described, the combination with a reed section, a sound board having a plurality of apertures closing one end of said section, reed trays disposed in said reed section and enclosing said apertures, and an apertured plate slidably mounted in each reed tray for opening and closing the communication between said tray and said board apertures, of a rock arm mounted in said reed sections and having one end operatively enegaging one end of said plate, means located on one of the side walls of said reed section for actuating said rock arm,

a rock shaft, an arm fixed at one end to the inner end of said shaft and having its opposite end connected to said means for actuating the same, another arm fixed to the outer end of said shaft, a shift key pivotally mounted on said sound board and disposed inwardly of said key board for depressing said last mentioned arm and actuating said rock shaft and parts associated therewith.

10. In an accordion of the character described, the combination with a keyboard, a reed section, a sound board having a plurality of apertures enclosing one end of said section, a reed tray disposed in said reed section and enclosing said apertures, and a plate slidably mounted in said reed tray for opening and closing the communication between said tray and said board apertures, of a rock arm pivotally mounted in said reed section and having one end operatively engaging said plate, means located on one of the side walls of said reed section and operatively connected to said rock arm, a rock shaft journaled transversely in said key board near said reed section side wall, an arm fixed to the inner end of said shaft and operatively engaging said means, another arm fixed to the outer end of said shaft, and a shift key disposed longitudinally above said sound board inwardly of said keyboard for actuating said outer arm.

11. In an accordion of the class described, the

combination with a keyboard, a reed section, and a sound board closing one end of said reed section, of a reed tray in said section, a slidable plate for controlling said reed tray, means in said reed section for operating said plate, said means including a pin extending outwardly through a slot in one of the side walls of said reed section, an oscillatable member mounted exteriorly on said slotted side wall and having one end fixed to the projecting end of said pin, a reciprocable member mounted on said slotted reed section side wall and adapted to engage said oscillatable member and move it alternately in opposite directions, a rock shaft journaled transversely in said sound board and having one end operatively connected to said reciprocablc member, an arm fixed on the opposite end of said shaft, and a shift key operatively mounted on said sound board and adapted to engage said last mentioned arm and actuate said'shaft and parts associated therewith.

12. In an accordion of the character described, a shift key mechanism comprising a depressible shift key bar disposed longitudinally of the accordion, a rock shaft disposed below and transversely of said key, an arm fixed to one end of said shaft and operable by said shift key, a second arm fixed to the other end of said shaft, a longitudinally movable member operable by said second arm, and means actuated by said longitudinally movable member and operatively associated with a slide plate of a reed section for operating said plate alternately in opposite directions at each depression of said shift key bar. 

